First decodes using 8-minute WSPR:
|
2012-09-21 00:00
|
DK7FC
|
0.137508
|
+7
|
0
|
JN49ik
|
1
|
DF6NM
|
JN59nj
|
175
|
91
|
|
2012-09-20 23:52
|
DK7FC
|
0.137508
|
+3
|
0
|
JN49ik
|
1
|
DF6NM
|
JN59nj
|
175
|
91
|
Between 23:36 and 23:43:20, Stefan was transmitting 8-times slow WSPR with low power on 136172 Hz. This was recorded here to an IQ file using SndInput from DL4YHF, and replayed 8x fast during the next 2-minute, slot starting
23:44. In the process the audio was frequency shifted from 670 to 2000 Hz, and added to the normal audio data for WSPR. Thus with the 4x acceleration, Stefan's transmission appeared 8 instead of 2 Hz above center.
This is all still a bit improvised, but the concept seems to work.
Best 73,
Markus (DF6NM)
